I used to buy custom pieces and needed one rather quick one time so ordered a Swiss lace stock. I will never go back to customs as my stocks are cut down to exact size and not sure why, but they last me way longer than I ever got from a custom. Just my opinion and experience.

As far as getting your cut in after receiving, my advice would be to go ASAP. If you attach without cutting in you will not be happy with the way it looks. The cut in will be 100x different. I've been wearing for little over a year now and when I got my first piece I was like what the hell is this, but the guys on here and other forums assured me would look good after cut in and have never looked back since.

Edit: Misunderstood your hair cut question. Thought you were asking how soon for cut in. I get my hair cut about every 6-8 weeks. If the place you are getting your cut in is satisfactory to you, should be half or less the cost of your cut in for just a haircut and bond. You could also buy a flowbee or robocut and do whenever you like.

As far as hair growing underneath, not really a big deal if reattaching every week or two. You will just shave what grows every de/re bond. The second picture you posted of hairstyle you wanted is the way I wear my hair although I cut it a little bit shorter on top. From looking at your pics although sides look a bit thin (in some pics) you could definitely pull similar style off but would go a bit shorter on top as well.

Lastly, 80 bucks for a bond and cut in is a great price, at least in NYC where I pay 2 1/2x that. The only thing I want to say is I saw you live in Australia. On another forum somebody was asking for stylist there and they were warned to stay away from a place that did cut ins and sold their own pieces. Guy said they intentionally screw up pieces they don't sell so you have to purchase one of theirs. Obviously the chances it's the place your going is slim but if you can name them can look and make sure.